C Syntax

FORTRAN Syntax

Description

When the system is in picking mode, and a subroutine draws in the
picking region, the contents of the
name stack are stored in a buffer, along with the number of names in the stack.

If a drawing primitive overlaps or intrudes upon the picking volume, a
hit has occurred. The hit is recorded only if the name stack has been touched since the last hit. Any of the subroutines loadname, pushname, or popname touch the name stack. The first hit after picking begins is always recorded.

A hit is recorded by placing the depth of the
name stack into the next vacant slot in the buffer, followed by the entire contents of the name stack. The bottom of the name stack is transferred to the buffer first, followed by the second from the bottom entry of the name stack, and so forth. In other words, from bottom to top is mapped to from left to right.

Parameter

Return Value

The number of times the name stack was written to the buffer. If the returned function value is negative, then the buffer was too small to contain all the readings from the name stack. The absolute value is the number of stacks actually recorded.

Example

The example C language program pick1.c calls the endpick subroutine to turn off picking mode.

Implementation Specifics

This subroutine is part of GL in the AIXwindows Environment/6000 Version 1, Release 2 with AIXwindows/3D Feature.